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Skipping school and how to reduce it? The value of information and incentivizing parents vs. children

 This is a guest post jointly authored by Damien de Walque and Christine Valente.
 
If one of our children is skipping school without our approval and if we have not excused him or her before, my wife and I quickly receive a text message (see screenshot below), an email and a phone call from the school district. A serious discussion in the evening will ensue.
 

 

What should you do when your random assignment gets compromised?

David McKenzie's picture

The New York Times recently had a piece on the retraction and re-issuance of a study in Spain based on a randomized trial of the Mediterranean Diet’s effect on heart disease. The original study was meant to be an individualized random assignment of 7,447 people aged 55 to 80 to one of three different diets – a control diet (advice to just reduce fat content), or two variants of the Mediterranean Diet (in which they were given free olive oil or free nuts). The study was originally published in the New England Journal of Medicine (NEJM) in 2013. The authors then appear to have been surprised to find their study on a list of suspicious trials.  There are several parts to this story I thought would be of interest for doing impact evaluations in development, which I discuss below.

Weekly links June 22: which countries are overrepresented in IEs? How many IEs have data available to replicate them? Mobile savings, and more...

David McKenzie's picture
  • In the Harvard Business Review, Blumenstock, Callen and Ghani summarize their work on using nudges to get government employees to save using mobile money in Afghanistan – “Over six months, the average employee who was enrolled to save by default accumulated an extra half-month’s salary in his or her savings account, relative to employees who had to opt in”
  • An intro to R for Stata users
  • The promise and perils of listening to parents – Sharon Wolf on ongoing efforts in Ghana to improve pre-school quality, and how trying to bring parents onboard backfired.
  • In the Journal of Development Effectiveness, Sabet and Brown track the continued growth of development impact evaluations: “Though we find early evidence of a plateau in the growth rate of development impact evaluations, the number of studies published between January 2010 and September 2015 account for almost two thirds of the total evidence base”. Lots of other interesting facts, including 45% of all impact evaluations occurred in just 10 countries, with Kenya and Uganda having the most impact evaluations per million population, and Sub-Saharan Africa the most commonly represented region – perhaps something for donors to think about...

Weekly links June 15: advice, humanitarian assistance RCTs, power calcs gone wrong, the CDD debate, and more...

David McKenzie's picture

Is grammar holding back efficiency and growth?

Markus Goldstein's picture
Ask a German to describe a bridge, and they are likely to use words like beautiful and elegant.   Ask a Spanish speaker, and they will use words like big and dangerous.   Now, ask them to describe a key.  The German will say hard and heavy while the Spanish speaker will say lovely and intricate.    Why?   According to work by Boroditsky and co-authors, that’s because in German the bridge takes a feminine article and the key takes the masculine.   And, as you may have guessed, the reverse is true in Spanish.  
 

Writing a Papers and Proceedings Paper

David McKenzie's picture

Ok, this is an even more specialized blogpost than usual, but I thought it might still be of use to some readers. I’ve received several variants of the following question from colleagues “I’m excited that my AEA session was accepted for the papers and proceedings. But how do I write a P&P paper without hurting my chances of also publishing the longer paper?” or “but the paper I have in that session is already forthcoming somewhere else, what should I write as the P&P?”.  I thought I’d offer my advice on this, since there doesn’t seem to be much written out there.

Weekly links June 8: are negative income taxes toxic, marshmallows and SES, psychometric credit, p-value hate, and more...

David McKenzie's picture
  • The Atlantic summarizes a new replication of the marshmallow test, “the new study finds limited support for the idea that being able to delay gratification leads to better outcomes. Instead, it suggests that the capacity to hold out for a second marshmallow is shaped in large part by a child’s social and economic background—and, in turn, that that background, not the ability to delay gratification, is what’s behind kids’ long-term success”
  • David Evans’ collection of logframes!
  • On the All About Finance blog, Claudia Ruiz and co-authors summarize their work in Peru on using psychometric scoring to extend credit to SMEs – using a regression discontinuity.
  • Sylvain Chabé-Ferret hates p-values so much he is writing 6 blog posts about it (post 1, post 2, post 3, post 4, others to come). I particularly recommend post 4, which has a nice illustration of the point that when samples are small, if you find a statistically significant effect, it is heavily biased: in his simulation “With N=100, the estimates that are statistically different from zero at the 5% level are 2 to 2.5 bigger than the true effect”.

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